Agricultural burning in Imperial Valley, California and respiratory symptoms in children: A cross-sectional, repeated measures analysis

Elizabeth M Kamai; Brandyn C Ruiz; Yoshira Ornelas Van Horne; Dayane Duenas Barahona; Esther Bejarano; Luis Olmedo; Sandrah P Eckel; Jill E Johnston; Shohreh F Farzan

doi:10.1016/j.scitotenv.2023.165854

Agricultural burning in Imperial Valley, California and respiratory symptoms in children: A cross-sectional, repeated measures analysis

Sci Total Environ. 2023 Nov 25:901:165854. doi: 10.1016/j.scitotenv.2023.165854. Epub 2023 Jul 28.

Authors

Elizabeth M Kamai¹, Brandyn C Ruiz², Yoshira Ornelas Van Horne³, Dayane Duenas Barahona², Esther Bejarano⁴, Luis Olmedo⁴, Sandrah P Eckel², Jill E Johnston², Shohreh F Farzan²

Affiliations

¹ Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA. Electronic address: Kamai@usc.edu.
² Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
³ Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA; Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY, USA.
⁴ Comite Civico del Valle, Brawley, CA, USA.

PMID: 37516194
PMCID: PMC10592232 (available on 2024-11-25)
DOI: 10.1016/j.scitotenv.2023.165854

Abstract

Burning of agricultural fields is an understudied source of air pollution in rural communities in the United States. Smoke from agricultural burning contains air toxics that adversely impact respiratory health. Imperial County in southeastern California is a highly productive agricultural valley that heavily employs agricultural burning to clear post-harvest crop remnants. We related individual-level exposure to agricultural burns to parent-reported respiratory symptoms in children. We leveraged the Children's Assessing Imperial Valley Respiratory Health and the Environment (AIRE) cohort of 735 predominantly Hispanic low-income elementary school students in Imperial County. Parents reported children's respiratory health symptoms and family demographic characteristics in questionnaires collected at enrollment and in annual follow-up assessments from 2017 to 2019. Permitted agricultural burns in Imperial County from 2016 to 2019 were spatially linked to children's geocoded residential addresses. We used generalized estimating equations to evaluate prevalence differences (PDs) in respiratory symptoms with increasing exposure to agricultural burning within 3 km in the 12 months prior to each assessment. Nearly half of children (346, 49 %) lived within 3 km of at least one agricultural burn in the year prior to study enrollment. In adjusted models, each additional day of agricultural burning in the prior year was associated with a one percentage point higher prevalence of wheezing (PD 1.1 %; 95 % CI 0.2 %, 2.0 %) and higher bronchitic symptoms (PD 1.0 %; 95 % CI -0.2 %, 2.1 %). Children exposed to four or more days of burning had an absolute increased prevalence of wheezing and bronchitic symptoms of 5.9 % (95 % CI -0.3 %, 12 %) and 5.6 % (95 % CI -1.8 %, 13 %), respectively, compared to no burn exposure. Associations with wheezing were stronger among children with asthma (PD 14 %; 95 % CI -1.4 %, 29 %). To our knowledge, this is the first U.S. study of agricultural burning and children's respiratory health. This work suggests that reducing agricultural burning could improve children's respiratory health.

Keywords: AIRE; Air pollution; Bronchitic symptoms; Wheeze.

Grants and funding

R01 ES029598/ES/NIEHS NIH HHS/United States